iNotify Man Page: Prefix Header + Tail Array vs C Structure

[Michael Titke <michael.tiedtke-X3bqsT2AMO4b1SvskN2V4Q@public.gmane.org>]

Hello!

The current version of the manual page describing /inotify/ (as well as 
the version installed with Ubuntu 15.04 frozen to Violet Indigo) 
contains a descriptive C structure describing the /inotify//messages/:

            struct inotify_event {
                int      wd;       /* Watch descriptor */
                uint32_t mask;     /* Mask describing event */
                uint32_t cookie;   /* Unique cookie associating related
                                      events (for rename(2)) */
                uint32_t len;      /* Size of name field */
                char     name[];   /* Optional null-terminated name */
            };

As part of the development of VSI I translated the above structure 
without much thinking into a corresponding byte structure description:

(define inotify-event-header
   (byte-structure-description
    (wd   int)
    (mask   4) ; [sic! that was an uint32]
    (cookie 4)
    (len    4)
    ;(name   pointer) ; That's not a pointer but an array: NAME_MAX + 1
))

Now while the prefix (or header) of the message is described adequately 
the specification of the tail array as a char name[] would in C be 
interpreted as a pointer onto a char. One might insert a length 
parameter like char name[NAME_MAX + 1] or exclude that tail array from 
the structure and describe the message in terms of /prefix/ or /header/ 
and /tail array/.

            struct inotify_event {
                int      wd;       /* Watch descriptor */
                uint32_t mask;     /* Mask describing event */
                uint32_t cookie;   /* Unique cookie associating related
                                      events (for rename(2)) */
                uint32_t len;      /* Size of name field */
                char     name[NAME_MAX + 1];   /* Optional 
null-terminated name */
            };

With that length parameter in the structure the size of the messages is 
described adequately but the actual length of the name might be confused 
with the maximum size which usually includes some (tail) padding.

I'm sorry but I don't know enough about /iNotify/ to craft a patch for 
this. Is this a datagram channel where half-read messages will vanish? 
Perhaps I should continue reading the manual page. :-)

Regards,
Michael

--
VSI: https://code.launchpad.net/viper-system-interface

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PS That's not really up to the standard but "... since hosts aren't 
required to relay mail at all ..." someone presumes something.
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